Adrian Chadd 6893df4146 Bring over interrupt mitigation changes from ath9k.
* The existing interrupt mitigation code didn't mitigate anything - the
  per-packet TX/RX interrupts are still occuring. It's possible this
  worked for the AR5416 but not any later chipsets; I'll investigate and
  update as needed.

* Set both the RX and TX threshold registers whilst I'm at it.

This is verified to work on the AR9220 and AR9160. I'm leaving it off
by default in case it's truely broken, but I need to have it enabled
when doing 11n testing or interrupt loads exceed 10,000 interrupts/sec.
2011-03-25 00:03:21 +00:00
..